One type of watercraft is the jet propelled type that is designed to be operated by a rider that is seated on the watercraft in a straddle-like fashion. This type of watercraft is propelled by discharging water out of a discharge nozzle located at the rear of the watercraft.
To provide steering for the watercraft, a steering nozzle is pivotably connected to the end of the discharge nozzle. The input for the pivot of the steering nozzle is provided by a steering handle pivotably mounted on the top of the watercraft. To steer the watercraft to the right, the rider turns the steering handle clockwise causing the steering nozzle to pivot counter-clockwise. The discharge of water out of the steering nozzle with the nozzle pivoted counter-clockwise causes the watercraft to yaw clockwise and turn to the right. A similar but opposite sequence is used to steer the watercraft to the left. Therefore, for a watercraft of the jet propulsion type to steer properly, a sufficient amount of thrust out of the steering nozzle is required.
The thrust of the watercraft is controlled by the rider through the use of a finger operated throttle lever pivotably mounted on the steering handle. The throttle lever is biased toward an idle position. To increase thrust of water out of the discharge nozzle, the rider presses down on the throttle lever with his finger. This pivots the throttle lever toward the wide open throttle position. To decrease thrust of water out of the discharge nozzle, the rider releases the throttle lever. Since the throttle lever is biased toward the idle position, without a force countering the bias, the throttle lever pivots toward the idle position. As the throttle lever pivots toward the idle position, the thrust of the water out of the discharge decreases.
While the decrease in thrust of water out of the discharge nozzle is desirable for slowing down the watercraft, the decrease in thrust of the water out of the discharge nozzle also decreases the steering capability of the watercraft since the thrust provides the steering for the watercraft.
This quick decrease in steering capability is partly problematic in situations in which an inexperienced rider attempts to avoid an obstacle directly in front of the watercraft. To properly avoid the obstacle, the rider should apply a constant pressure on the throttle lever while simultaneously turning the steering handle. However, an inexperienced rider may release the throttle lever to slow the watercraft quickly while simultaneously turning the steering handle in an attempt to maneuver around the obstacle. In such a situation, the rider may not be able to maneuver around the obstacle since steering capability has been decreased.
This decrease in steering capability is also problematic for the rider to maneuver the watercraft for docking the watercraft. Since the docking procedure usually occurs with the watercraft traveling at a low speed, the rider may release the throttle lever while attempting to dock the watercraft. However, with only idle thrust provided to steer the watercraft, steering capability may not be adequate to dock the watercraft.
The present invention is directed toward a thrust system for a watercraft of the jet propulsion type comprising a steering mechanism, a throttle control mechanism, a thrust mechanism and a controlled thrust steering system. The steering mechanism has a straight-ahead position. The steering mechanism is able to rotate in a clockwise direction from the straight-ahead position and in a counter-clockwise direction from the straight-ahead position. The throttle control mechanism is mounted on a steering handle of the steering mechanism. The throttle control mechanism moves toward an idle position after the throttle control mechanism is released. The thrust mechanism provides jet propulsion thrust for the watercraft. The controlled thrust steering system causes the thrust mechanism to increase thrust or inhibits the thrust from decreasing below a steerable thrust upon rotating the steering mechanism in the clockwise direction or the counter-clockwise direction. The controlled thrust steering system also causes the throttle regulator to decrease thrust upon rotating the steering mechanism toward the straight-ahead position.